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Wedge TR7 now starts [hard] and will not continue to run

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Sunset7

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Hey guys - update on the new 80 model cal spec injected 7 ordeal.

I got it started, and actually drove it (woo hoo!) but it would not stay running on its own when you slow down to stop.

Now, after setting for a few weeks, I can't get it to start at all.

I've pretty much checked everything out, and now I am thinking it might be the injectors leaking.

Any ideas?

You injected guys don't take offense, but I am really considering just pulling all the injection crap off and installing a set of stock Strombergs that I have laying around. Does anyone know of EXACTLY what would have to be replaced, other than the carbs an manifold? Is this easy or hard to do.

Would you replace the stock fuel injection fuel pump, or just put a regulator in line to tone down the high pressure from the stock pump?

I know from previous experience in modifying cars that its the little stuff that can drive you nuts, like a sender or fitting that is just in the wrong place, or a hose that now won't reach etc.

Any and all comments and advice is appreciated.

Thanks!

I bought this car in Sept. and haven't got to drive it yet (more than just down the street and back)
 
If you've only had this car since September it is still too early to panic. It would be regressive to go to the trouble of putting carburetors on. The Bosch FI on your car has been used in various configurations by different manufacturers on virtually every vehicle built in the world since yours was built. Diagnoses with FI is not that different than with carbs. It's still fuel, compression, and ignition. Is the fuel pump running when cranking? Does it continue to run when the starter switch is released? Is fuel getting to the injectors? If you hot wire the pump directly from the battery, what is the result? Keep it simple, logical and systematic. A shotgun approach might fix it without yeilding an answer as to what the problem was to be avoided in the future. Do not despair, there are several on this forum that have been through the same trials, I think I can speak for all of them that the FI is worth sticking with once it's sorted out. The problem isn't with the FI so much as the age of the systems, from the fuel tank through the exhaust. Good Luck and endeavor to persevere.
 
Agreed. Don't panic.

In fact once you are past the scary "fuel injection" label it's easier to diagnose than the stroms. I have both stombergs on the 76 and PI on the 81.

>> injectors leaking.

No - this is last on the list.

1) Ensure fuel pressure. Disconnect a line and check. It's very high pressure so will shoot out like a hose.
2) Check pressure before and after the regulator.
3) Replace the fuel filter regardless.
4) Check electric connections. Clean all. A poor ground connection is necessary.
5) Do you have false air anywhere? The slightest leak will upset things. Those old hoses are notorious and can be fixed temporarily with duct tape.

Believe it or not this same injection system was used on millions of cars so a volkswagen mechanic can handle the checking if you need it. More people are experts on Bosch Fuel Injection than Stromberg catbs.

Stick with it. The driveability of the PI model is waaaay above the carb version. Trust me that trying to plumb back on used carbs is more expensive and more trouble that fixing the PI.
 
Hey, look on the bright side ... at least your 7 starts -- you're ahead of me by a great distance!!!
/ubbthreads/images/graemlins/wink.gif
 
barnes and noble has a great book on the bosch fuel injection systems. about $20, covers most variations of the jtronics system (even those on toyotas, bmw's and volvos).i've also found lots of good advice on the jtronics by googling.
 
Sorry for not answering sooner, but was out of town with only minimal internet access....

Assuming that you've got all the basics, e.g. spark, fuel, etc., look at the thermotyne switch and cold start injector. The Bentley manual has some good testing steps for them. I would suspect that the cold start injector is bad, as my car had similar problems this past spring. Had to floor it to get it to start, and then pump the pedal to keep it going. Replaced the cold start injector, after verifying the thermotyne switch was good, and no problems since...

As far as converting to carbs...read some of the threads here from people who've had carb problems. Also, there's a different fuel tank (although you could probably plug the second hole in yours), new intake manifold, and air delivery to worry about. Not to mention making major changes in the wiring (always a way to invite the Prince of Darkness to visit you) Probably not the cheapest or easiest conversion. This system generally works really good, and there's little to tinker with once it's set up right.
 
Thanks to all for giving me hope, and telling me to abandon the idea of going back to the Stroms.

Finally quit raining here (no garage yet) and I got to tinker with it a bit more.

pulled fuel line off of regulator,
turned key to "ON" - NOTHING.Turned key to crank, gas shoots out?????

WHY doesn't the pump come on at "ON" but does at crank?

Looks like someone monkeyed with the wiring around where the inertia switch SHOULD be. ( I cannot find it ) AND under the dash coming out of the steering column.

I think the previous owner had a "mechanic" trying to fix the turn signal switch by cutting and jumping wires.

I am going to look at it and see if he cut anything going from the ignition switch to the fuel pump / or relay.

ANY IDEAS????

I have replaced the Thermotime switch and it helped some, so I will probably go ahead and buy the cold start injector once I get the fuel pump worked out.

Thanks again guys!!
 
Mark's right about the cold injector. I'm still suspicious of overall fuel pressure and remind you to change the filter regardless. You may need to get a gauge on the fuel line to be sure. It's frightenly high pressure if you just pull the line off while the pump is running. 32-36 lbs I believe.

If someone has been messing with the inertial switch this may do it. Please replace it and make sure it does what it is designed to do. Otherwise in an accident there will be the wrong kind of Texas barbeque.
 
Thanks.

I have replaced the fuel filter as a matter of course.

According to my Bentley manual, this car has NO switch where the manual shows the inertia switch to be. Can I use a racing one like the universal fit type in the Summit Racing Catalog, or do I have to have the NOS Triumph one? (Summit one is WAY cheaper I think)

Where is the fuel pump relay? By the fuse panel in the glove box?

You know, the really weird thing is that I actually had the thing running once, and drove it down the road for about 15 minutes, brought it back, parked it, then it wouldn't start at all.

If the pump or wiring was bad, why did it run then?

(I know that I had to crank the crap out of it to get it to start, which should go away when I get it wired properly)

Thanks again!
 
Cranking the starter puts power directly to the pump. The dual relay in front of the glove box is supposed to switch power to the pump once the engine starts. The inertia switch is easily bypassed by connecting the two wires that go into it. One is a LGW ( light green with white tracer) the other a W or white wire. Hang in there, your gonna be OK.
 
[ QUOTE ]
According to my Bentley manual, this car has NO switch where the manual shows the inertia switch to be. Can I use a racing one like the universal fit type in the Summit Racing Catalog, or do I have to have the NOS Triumph one? (Summit one is WAY cheaper I think)


[/ QUOTE ]

I would get the OEM one...it's not that expensive (about $40). Got mine last year from Wedgeparts. Doing the bypass thing is OK for testing, but if I get in a crash, I want my fuel pump turned off, as I don't want a Texas Barbeque.


[ QUOTE ]
Where is the fuel pump relay? By the fuse panel in the glove box?


[/ QUOTE ]

The combined relay is located behind the glove box, sort of under the fusebox.
 
>>weird thing is that I actually had the thing running once

I agree that this puts most of the advice thus far a little off. Any of the standard things with relays, pumps and an inertia switches *should* mean it wouldn't have run at all. That was what behind my pushing the fuel pressure and filter stuff.

You mentioned the new cold switch 'helped'. What do you mean 'helped' ?

You're sure of course you have real spark and the plugs are OK ?

Next steps are to hook a VOM to an injector lead and make sure you've got juice in a nice rhythmic way as you crank. You could pull one injector and make sure there's a good spray but the odds of all four packing it in are low.

Do you smell gas ? I still think you're not getting gas for some reason.
 
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